Vibrations when driving

[65coronet440]

I have been rackin my head on this. i have a pulsing vibration when driving. i recently replaced the shocks on my 65 coronet 440 thinking that this would fix the problem and it partially did, however i still have this vibration. best way i can describe it is that its like the shivers (when u get cold) it is rhythmic, in a sense.couple seconds of "the shiver" the couple sec of nothing and then the shivering vibration...i can see the hood vibrate, the wipers vibrate, my steering wheel vibrates, the dash vibrates, i can feel it under my feet.. but if i gun it for a sec it will go away and then when i let off its back again. wheel balancing???
please help i want to drive my car without worry!

Thanks

 

[FatJack]

Try different tires on the front and have a good alignment shop check the front end parts.

 

[HitIt]

U-joints going out?

 

[Red63440]

You may also want to check your drive shaft, it could be out of balance.

 

[65coronet440]

Try different tires on the front and have a good alignment shop check the front end parts.

I dont have another set, I did check all the suspension components when i changed the shocks and gave everything a good tug, and all seemed ok, but maybe a professional diagnostic wouldn't hurt. BTW the alignment seems good, straight as a arrow.

 

[65coronet440]

You may also want to check your drive shaft, it could be out of balance.

The driveshaft was replaced last year during racing season, and i remember when my dad was racing it , it was fine before the new driveshaft.... this could be a good insight!! Because eversince that new driveshaft it has been vibrating.....So where do i take the driveshaft to get it balanced?

 

[Dodge 330]

Yep, I was going to say driveshaft/u-joint.

I had one that was prepped by Inland and THOUGHT they balanced and checked for runout. Well, they did neither and it was a pulsating vibration that woud only really appear around 70 mph!

New shaft, no problem!

I get mine done locally at a shop called Powerdrive.

 

[Red63440]

OK, what do I win?????

 

[65coronet440]

OK, what do I win?????

You win must utmost respect Sir!

 

[65coronet440]

Yep, I was going to say driveshaft/u-joint.

I had one that was prepped by Inland and THOUGHT they balanced and checked for runout. Well, they did neither and it was a pulsating vibration that woud only really appear around 70 mph!

New shaft, no problem!

I get mine done locally at a shop called Powerdrive.

It is a new driveshaft and ujoints, it was replaced after the original one snapped and took out the tailshaft.... but the regular mechanic was a snake, so im questioning everything he has done. So can a speed shop re-balance the driveshaft that i have in the car now, or do i need to buy another one?

 

[Red63440]

LMAO...now I feel 20 years older...gee that would make me just about 81.:sleepy2:
Just hope thats the problem and glad to help...IF i'm right.

 

[Red63440]

It is a new driveshaft and ujoints, it was replaced after the original one snapped and took out the tailshaft.... but the regular mechanic was a snake, so im questioning everything he has done. So can a speed shop re-balance the driveshaft that i have in the car now, or do i need to buy another one?

Most shops that build and alter drive shafts can do what you need. Throwing one samll weight can casuse what you are describing.

 

[74sundance]

You didn't say weather or not the vibration happens as soon as you start driving or after driving for a while so I'll just put this out there just in case....Before you pull the drive shaft you might want to test your trans/torque converter.
Transmissions can shudder in a very similar manner to torque converters. To determine whether the shudder is tranny or TC related, drive the car for a little while until it starts to shudder and immediately park it. With your foot on the brake, put the transmission in Drive, and apply light throttle. If you feel shuddering, then it's the Torque converter; if not, then the problem is within the transmission(probably a sticky valve).This test will rule out(drive shafts,tires,suspension,bent rims,bad body mounts,rear gear,and all other rolling causes of vibrations.If it's not the problem then at least you know your tranny is good
If it doe's vibrate during the test its an easy fix unless there is physical damage to the converter or transmission. Once the transmission fluid has been overheated enough times, it becomes permanently de-polymerized and needs to be replaced. You could replace it with Ford Type F transmission fluid,it has friction modifiers that the stock Dextron doesn't have. It wouldn't be a bad idea to use a trans cooler if this fixes your problem.

 

[65coronet440]

it doesn't start vibrating immediately, i have done the park+throttle test and its good, it is also a new torque converter.... it usually starts around 30-35mph

 

[Cranky]

Could be drive shaft run out...place the rear axle on jack stands high enough to where you can see the shaft spinning without getting under the car then have someone turn the wheels while you watch the shaft spin. It's almost impossible to have '0' run out but more than .030" probably needs to be looked at. Has the angles changed when it was replaced?

 

[wedgie]

Had the same issue with my street driven '65. After correcting the pinion angle to 3* nose down, in relation to the crankshaft, problem gone. Based on your sequence of events though, it does sound like you have a driveshaft problem. Be sure that your shaft is not too short as well as being true and balanced.

 

[moparman400]

Tires,tires,tires....... if the shocks calmed it down abit, i would put the car on jack stands and spin the tires. Look for a bulge in the ply's.

 

[65coronet440]

Tires,tires,tires....... if the shocks calmed it down abit, i would put the car on jack stands and spin the tires. Look for a bulge in the ply's.

Then i would need a new tire if there is a buldge...correct, or would that mean a rim is bent and both would need replacing?

 

[65coronet440]

Ah ha!!!!!

So i jacked up the rear end and spun the back tires the best i can. and the driveshaft looked straight, u joints looked new and greased. so i lifted up the passangerside front tire and spun it and found what looks like a BENT rim!!!!. she was all kinds of wobbling, almost 1/2"... so im taking it in to a shop that can confirm it tomorrow, and then i guess ill be ordering a new rim and keeping my fingers crossed... i did notice that the drum was TOO eay to take off, just about fell in my lap! but i spun the axle and didn't see and varience of a bent axle.. so im hoping that is all it is and i can finally drive this 440 over 35mph..lol...ill keep you all posted, and thanks for the guidence on this..

 

[shag766]

I dont have another set, I did check all the suspension components when i changed the shocks and gave everything a good tug, and all seemed ok, but maybe a professional diagnostic wouldn't hurt. BTW the alignment seems good, straight as a arrow.

its a rotateing problem. it comes and goes and has a lot of vibration to make **** shake. if it was front end it couldn't shake enough to make things vibrate or you would be in the ditch. just my thought. rick